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A D V A N C E D
M A T E R I A L S
&
P R O C E S S E S |
S E P T E M B E R
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n the chemical, oil and gas, fossil fuel,
and nuclear power industries, pipe
and equipment corrosion is a major
cause of leaks and other issues that can
lead to early replacements, unplanned
outages, and incidents potentially
resulting in plant and factory damage
and injury to workers. To learn more
about this topic,
Advanced Materi-
als & Processes
spoke with Brian Wil-
son, business development manager,
energy markets, portable analytical
instruments, for Thermo Fisher Scien-
tific, about the causes and dangers of
infrastructure corrosion and how por-
table analysis tools can help facilities
save time and improve safety.
Can you discuss the importance of
analyzing element concentrations in
industrial infrastructure?
Throughout the chemical, oil
and gas, fossil fuel, and nuclear power
industries, there is an increased focus
on measuring residual elements in the
carbon and microalloyed steels used
in piping and components. It is imper-
ative to understand the expected life
and performance of the infrastructure.
As carbon steel manufacturing has
become more dependent on recycled
metal scrap, residual element concen-
trations in materials have increased.
These can significantly impact mate-
rial properties—including corrosion
resistance—with regard to melting and
maintenance of piping and compo-
nents. We have seen elemental analysis
become increasingly important for both
installed and newly purchased indus-
trial framework and equipment.
Is the need for materials analysis
greater today than in the past?
Industrial infrastructure across the
country is aging, with many oil refining
and petrochemical sites using the same
pipe they did 30 or 40 years ago. As
piping and components age, the abil-
ity to verify their elemental makeup is
essential in order to prevent leaks and
ruptures that could adversely impact
worker safety and plant reliability. In
the past, metals analysis primarily
focused on heavy elements that made
up the largest proportion of the alloy
matrix. Today, we are learning more
about corrosion mechanisms and the
need to analyze residual, or trace ele-
ments, which require more sensitive
testing technology to measure. It is
critical that refineries and plants imple-
ment a material verification program
(MVP) proactively—before a costly fail-
ure occurs—as infrastructure ages.
What are the main causes of corro-
sion across the industrial sectors?
A number of variables cause
corrosion at industrial sites, mainly
stemming from sustained equipment
use and elevated levels of residual
elements. One cause, in particular, is
flow-accelerated corrosion. This occurs
when the protective oxide layer on the
inside surface of carbon and low alloy
steel pipe dissolves as iron oxides that
naturally form on the pipe’s exposed
surface are removed by hot water flow-
ing over it. Elevated levels of residual
elements such as chromium, copper,
and nickel can also cause corrosion in
hydrofluoric acid alkylation units, while
carbon steels with low silicon content
TECHNICAL SPOTLIGHT
USING ELEMENTAL ANALYSIS TO
MANAGE INDUSTRIAL CORROSION
As industrial infrastructure continues to age, the risk of corrosion-related
incidents becomes greater, increasing the need for detailed analysis of
residual elements in steel framework and equipment.
Thermo Scientific Niton XL5 XRF analyzer
inspects finished welds in steel piping.
can corrode at an accelerated rate when
exposed to hydrogen containing sulfur
compounds at elevated temperatures.
Using materials analysis technology,
technicians can measure the elemental
composition of piping and components
and detect the presence of alloying
elements (such as silicon, vanadium,
niobium, and titanium) that can reduce
the rate of deterioration, in addition to
residual elements that can contribute
to corrosion.
Several technologies are available
to analyze the elemental content
of metals. Which approach do
you recommend for industrial
infrastructure?
For metals analysis, materials
characterization is generally performed
using methods such as x-ray fluores-
cence (XRF), optical emission spec-
trometry (OES), and lab analysis. Over
the years, the materials characteri-